JSplitPane does not paint transparent controls properly

Name: dbT83986 Date: 01/10/99


Placing a transparent control in a JSplitPane causes severe painting
problems. Its probably because the JSpiltPane does not appear to
clear its own background properly. Try the following test case...

// Foo.java

import java.awt.*;
import javax.swing.*;

public class Foo extends JFrame {
    
    public static void main(String[] args) {
        (new Foo()).show();
    }
    
    private Foo() {
        super("Painting Test");
        
        JLabel left = new JLabel("Left Component");
        JLabel right = new JLabel("Right Component");
        
        //left.setOpaque(true); // default is false
        //right.setOpaque(true);

        // VERTICAL_SPLIT has the same results
        JSplitPane split = new JSplitPane(JSplitPane.HORIZONTAL_SPLIT, left, right);
        
        setContentPane(split);
        setSize(400,300);
    }
    
}

1 - Compile and run the above program.

2 - Drag the splitter side-to-side. Notice the painting problems.

3 - Un-comment the setOpaque(true) lines. Recompile.

4 - Run the program and perform the same tests. Notice that the
    problem is gone.
(Review ID: 52344)
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